The surgical management of symptomatic tetralogy of Fallot in infants is debatable. From November 1986 to August 1990, 21 infants under 10 kg of the body weight with tetralogy of Fallot underwent primary repair. Mean body weight was 8.6$pm$1.40kg. All the patient were clubbing and there were cyanotic except for 1 patient. Transannular patch was laid down in 8 patients. Right ventricular outflow patch was used with Goretex but pericardial patch was utilized in 3 patients at the initial period of operation. Incidence of the complications following total correction of tetralogy of Fallot was more frequent in the patients placed with transannular patch compared to the patients with right ventricular outflow tract patch. Two deaths occurred in the 21 patients, Hospital mortality was 9.4%, but there were no operative deaths in the patients who transannular patch was laid down. Causes of deaths were low cardiac output.